为什么我们需要在C ++中初始化int变量？

Question

为什么我们需要在类下初始化int变量而不是其他变量。 谁能用普通的简单形式解释？

#include <iostream>
using namespace std;

class Car{
public:
    string brand;
    string name;
    int year{};
};

int main() {
    Car c1;
    c1.brand = "Pagani";
    c1.name = "Honda Zuyara R";
    c1.year = 2015;

    Car c2;
    c2.brand = "Porche";
    c2.name = "Carrera";
    c2.year = 2003;

    cout << "Chaman's Car " << c1.brand << ends <<c1.name << ends << c1.year << endl;
    cout << "Mihir's Car " << c2.brand << ends <<c2.name << ends << c2.year << endl;
}